From 3fa6a3fadcbf7be764bac60484c8b4b39d4c74e5 Mon Sep 17 00:00:00 2001
From: Casey Bodley <cbodley@redhat.com>
Date: Wed, 3 Jan 2018 14:34:41 -0500
Subject: [PATCH 1/2] rgw: change ObjectCache::lru from deque back to list

ObjectCacheEntry stores an lru_iter into this lru, and depends on that
iterator remaining valid as other entries are inserted/erased

Fixes: http://tracker.ceph.com/issues/22560

Signed-off-by: Casey Bodley <cbodley@redhat.com>
---
 src/rgw/rgw_cache.cc | 4 ++--
 src/rgw/rgw_cache.h  | 8 ++++----
 2 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/src/rgw/rgw_cache.cc b/src/rgw/rgw_cache.cc
index 43c03ec5ecf..779a569625c 100644
--- a/src/rgw/rgw_cache.cc
+++ b/src/rgw/rgw_cache.cc
@@ -209,7 +209,7 @@ void ObjectCache::remove(string& name)
 }
 
 void ObjectCache::touch_lru(string& name, ObjectCacheEntry& entry,
-			    std::deque<string>::iterator& lru_iter)
+			    std::list<string>::iterator& lru_iter)
 {
   while (lru_size > (size_t)cct->_conf->rgw_cache_lru_size) {
     auto iter = lru.begin();
@@ -249,7 +249,7 @@ void ObjectCache::touch_lru(string& name, ObjectCacheEntry& entry,
 }
 
 void ObjectCache::remove_lru(string& name,
-			     std::deque<string>::iterator& lru_iter)
+			     std::list<string>::iterator& lru_iter)
 {
   if (lru_iter == lru.end())
     return;
diff --git a/src/rgw/rgw_cache.h b/src/rgw/rgw_cache.h
index 880001647af..b6066b6b544 100644
--- a/src/rgw/rgw_cache.h
+++ b/src/rgw/rgw_cache.h
@@ -128,7 +128,7 @@ WRITE_CLASS_ENCODER(RGWCacheNotifyInfo)
 
 struct ObjectCacheEntry {
   ObjectCacheInfo info;
-  std::deque<string>::iterator lru_iter;
+  std::list<string>::iterator lru_iter;
   uint64_t lru_promotion_ts;
   uint64_t gen;
   std::vector<pair<RGWChainedCache *, string> > chained_entries;
@@ -138,7 +138,7 @@ struct ObjectCacheEntry {
 
 class ObjectCache {
   std::unordered_map<string, ObjectCacheEntry> cache_map;
-  std::deque<string> lru;
+  std::list<string> lru;
   unsigned long lru_size;
   unsigned long lru_counter;
   unsigned long lru_window;
@@ -151,8 +151,8 @@ class ObjectCache {
   ceph::timespan expiry;
 
   void touch_lru(string& name, ObjectCacheEntry& entry,
-		 std::deque<string>::iterator& lru_iter);
-  void remove_lru(string& name, std::deque<string>::iterator& lru_iter);
+		 std::list<string>::iterator& lru_iter);
+  void remove_lru(string& name, std::list<string>::iterator& lru_iter);
   void invalidate_lru(ObjectCacheEntry& entry);
 
   void do_invalidate_all();

From 25b27b5c9d3f5a82769d06d92b9ba59038952ce8 Mon Sep 17 00:00:00 2001
From: Casey Bodley <cbodley@redhat.com>
Date: Wed, 3 Jan 2018 16:29:32 -0500
Subject: [PATCH 2/2] rgw: add invalidate_lru() call back to ObjectCache::put()

the removal of this line was causing s3test failures independently of
the change from list-deque

Signed-off-by: Casey Bodley <cbodley@redhat.com>
---
 src/rgw/rgw_cache.cc | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/rgw/rgw_cache.cc b/src/rgw/rgw_cache.cc
index 779a569625c..48d3c540877 100644
--- a/src/rgw/rgw_cache.cc
+++ b/src/rgw/rgw_cache.cc
@@ -134,6 +134,8 @@ void ObjectCache::put(string& name, ObjectCacheInfo& info, rgw_cache_entry_info
   ObjectCacheEntry& entry = iter->second;
   ObjectCacheInfo& target = entry.info;
 
+  invalidate_lru(entry);
+
   entry.chained_entries.clear();
   entry.gen++;